This circuit was obtained from Electronics Now magazine, July 1995. The triac depends on the heating element current, and the sensor will determine the adjustment potentiometer.
In the figure we show a timer, this simple one with only one of the four gates of integrated...
This circuit is a sensor for photodiodes that can be used in optical couplers, encoders and other...
This crystal tester was found on a 90s Ham Radio. Transistors are commonly used. The circuit is for...